Various types of organic, metalloorganic and inorganic materials such as polymeric sulfur nitride, polyacetylenes, polyphenylenes, polypyrroles, polythiophenes, polyphenylene sulfides and ion-radical salts are known which have unusual, highly anisotropic and potentially useful electrical, optical and/or magnetic properties [J. T. Devreese, et al., eds., "Highly Conducting One-Dimensional Solids", Plenum Press, New York (1979); W. E. Hatfield, ed., "Molecular Metals", Plenum Press, New York (1979); J. B. Torrance, "The Difference Between Metallic and Insulating Salts of Tetracyanoquiniodimethane (TCNQ): How to Design an Organic Metal", Accts. Chem. Res., 12, 79 (1979); J. S. Miller, et al., eds., "Synthesis and Properties of Low-Dimensional Materials", Ann. NY Acad. Sci., 313 (1979); H. J. Keller, ed., "Chemistry and Physics of One-Dimensional Metals", Plenum Press, New York (1977)]. Such materials have stimulated significant research activity in respect to the basic chemistry and physics of such materials. Furthermore, substantial efforts have been directed toward applications utilizing such materials, such as sensors [S. Yoshimura, et al., "Solid State Reactions in Organic Conductors and Their Technological Applications", Ann. NY Acad. Sci., 269 (1979); S. D. Senturia, et al., "The Charge-Flow Transistor: A New MOS Device", Appl. Phys. Lett., 30, 106 (1977)], rectifiers [A. Aviram, et al., "Molecular Rectifiers", Chem. Phys. Lett., 29, 27 (1974)], switching devices [R. S. Potember, et al., "A Reversible Field Induced Phase Transition in Semiconducting Films of Silver and Copper TNAP Radical-Ion Salts", J. Am. Chem. Soc., 102, 3659 (1980)], photoresists [Y. Tomkiewicz, et al., "Organic Conductors as Electron Beam Resist Materials", Extended Abstracts, Electrochemical Society Spring Meeting, St. Louis, May, 1980, No. 63.], fuel cells, chemoselective electrodes [S. Yoshimura, "Potential Applications of Molecular Metals", Plenum Press, p. 471, New York (1979); C. D. Jaeger, et al., "Electrochemical Behavior of Donor-Tetracyanoquinodimethane Electrodes in Aqueous Media", J. Am. Chem. Soc., 102, 5435 (1980)], solar energy conversion elements [C. K. Chiang, et al., "Polyacetylene, (CH).sub.x : n-type and p-type Doping and Compensation", Appl. Phys. Lett., 33, 78 (1978); M. Ozaki, et al., "Semiconductor Properties of Polyacetylene p-(CH).sub.x : n-CdS Heterojunctions", J. Appl. Phys., 51, 4252 (1980)] and electrophotographic devices, as well as durable synthetic materials to replace metals [E. M. Engler, et al., "Potential Technology Directions of Molecular Metals", Plenum Press, p. 541, New York (1979)]. However, despite the scientific advances which have been achieved, understanding and ability to exert chemical or manufacturing control in the practical utilization and application of such materials is at a relatively primitive level, thus representing a barrier to practical utilization of organoconductive materials. Major difficulties in the utilization of such organoconductive materials may include undesirable physical or mechanical properties of the material itself, instability of the material with respect to air or moisture, adverse effects of processing steps on conductivity, thermal intractability or instability, and/or insolubility in common solvents. In this latter regard, processing techniques such as fiber spinning and film casting or extrusion which are important for practical applications, are only possible if the material can be melted or brought into the solution phase.
Molecular arrays of planar, highly electron delocalized, polarizable molecules which form mixed valence, stacked crystalline lattices, such as metallophthalocyanine halides (e.g., nickel phthalocyanine iodides) exhibit significant low dimensional (e.g., substantially one-dimensional along the stacking direction) electrical conductivity and have desirable thermal stability, but are not readily obtained in desired forms or structures for practical use. In such stacked, electrically conductive molecular arrays, the subunit component moieties are positioned in close spatial proximity, and in crystallographically similar environments, with sufficient intermolecular orbital overlap to provide a continuous electronic pathway for carrier delocalization. Substantial research effort has been applied to the theoretical understanding of the properties and conductive mechanism of such materials [T. J. Marks, et al., Chapter 6, "Highly Conductive Halogenated Low-Dimensional Materials in Extended Linear Chain Compounds", Vol. 1, Plenum Press (1982), J. S. Miller, ed.]. The properties of such materials are typically measured from compressed pellets or carefully grown crystals.
Low-dimensional mixed-valent arrays of planar, conjugated metallomacrocyclic donor moieties such as glyoximates [M. A. Cowie, et al., "Rational Synthesis of Unidimensional Mixed Valence Solids. Structural, Spectral and Electrical Studies of Charge Distribution and Transport in Partially Oxidized Nickel and Palladium Bisdiphenylglyoximates", J. Am. Chem. Soc., 101, 2921 (1979); T. J. Marks, et al., "Assessing the Degree of Partial Oxidation in One-Dimensional Conducting Iodides", J. Chem. Soc., Chem. Commun., 444 (1976); L. D. Brown, et al., "Rational Synthesis of Unidimensional Mixed Valence Solids, Structure-Oxidation State-Charge Transport Relationships in Iodinated Nickel and Palladium Bisbenzoquinodioximates", J. Am. Chem. Soc., 101, 2937 (1979)], phthalocyanines [J. L. Petersen, et al., "A New Class of Highly Conductive Molecular Solids: The Partially Oxidized Phthalocyanines", J. Am. Chem. Soc., 99, 286 (1977); C. S. Schramm, et al., "Chemical, Spectral, Structural and Charge Transport Properties of the `Molecular Metals` Produced by Iodination of Nickel Phthalocyanines", J. Am. Chem. Soc., 102, 6780 (1980)], and tetraazanulenes [L. S. Lin, et al., "New Class of Electrically Conductive Metallomacrocycles: Iodine-doped Dihydrodibenzo[b,i][1,4,8,11]tetraazacyclotetradecine Complexes", J. Chem. Soc. Chem. Commun., 954 (1980)] having an MN.sub.4 planar ligand core structure have been extensively studied by reason of their electrically conductive properties. These cofacially stacking materials are cocrystallized with appropriate acceptor moieties such as bromine or iodine oxidants. When successful, such cocrystallization may provide a crystal structure composed of segregated (i.e., donors and acceptors in separate columns), partially oxidized metallomacrocyclic stacks and parallel arrays of halide or polyhalide counterions. The cofacially stacking subunits of the metallomacrocyclic stacks generally have fractional valence as a consequence of incomplete charge transfer from the cofacially stacking donor subunits to the associated acceptor moieties. For example, nickel phthalocyanine iodide [Ni(Pc)]I.sub.1.0 may be crystallized in stacks of rotationally staggered cofacially arrayed Ni(Pc).sup.+0.33 columns surrounded by parallel chains of I.sub.3.sup.- counterions in which conductivity is predominantly a ligand-centered phenomenon along the stacking direction of the nickel phthalocyanine columns.
Unfortunately, the lattice architecture of ionicly bonding materials depends upon the largely unpredictable and uncontrollable forces that dictate the stacking patterns, the donor-acceptor orientations, and the stacking repeat distances, such that a common pitfall in the design of new materials is that segregated stacks do not form. This problem severely limits the ability to design and tailor microstructures which lead reliably to electroactive molecular assemblies. Moreover there are substantial difficulties in providing such material in useful form. Furthermore, while such materials may be provided in powder or larger crystalline form, or in evaporated film form, these materials tend to be frangible and to have limited mechanical strength.
Control of cofacial stacking may be carried out by covalently bonding macromolecular subunits in cofacial stacking array, and substantial work has been carried out in the provision of covalently bonded, cofacially stacking polymers such as Group IV metallophthalocyanine, porphyrin and tetraazaannuelene polymers [R. D. Joyner, et al., "Germanium Phtalocyanines", J. Am. Chem. Soc., 82, 5790 (1960); M. K. Lowery, et al., "Dichloro(phthalocyanino)silicon" Inorg. Chem., 4, 128 (1965); W. K. Kroenke, et al., "Octahedral Silicon-Oxygen, Germanium-Oxygen, and Tin-Oxygen Bond Lengths from Interplanar Spacings in the Phthalocyanino Polymers (PcSiO).sub.x, (PcGeO).sub.x, and (PcSnO).sub.x ", Inorg. Chem., 2, 1064 (1963); Marks, et al., supra], particularly including polysiloxane and polygermyloxane stacking stabilized polymers, and fluoro-aluminum phthalocyanine polymers, such as [Al(Pc)F].sub.n and [Ga(Pc)F].sub.n, which are isoelectronic therewith [U.S. Pat. No. 4,304,719].
The covalent bonds which hold such cofacial arrays together are significantly stronger than packing, van der Walls, and band formation forces of ionicly bonding cofacially stackable materials which do not utilize such covalent stacking stabilization. However, such materials are similarly typically formed and studied as powders, particles or compressed pellets, and the practical utilization of such materials has been restricted for reasons including the lack of practical fabrication methods for these materials.
There is accordingly a need for methods and compositions for fabricating cofacially stacking electroconductive materials such as phthalocyanines into electroconductive articles having desirable thermal, hydrolytic and/or oxidative stability in addition to desirable mechanical and electroconductive properties, and for electroconductive compositions, articles and devices utilizing such cofacially stacking electroconductive materials.